Electrolytic Ni-Cr alloy foil, method for manufacturing the same, and composite components

Abstract

To provide an electrolytic Ni-Cr alloy foil that can be produced by electrolysis.SOLUTION: An electrolytic Ni-Cr alloy foil is composed of Ni, Cr and impurities and has a brightness L* of 30 or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to electrolytic Ni-Cr alloy foil, a method for manufacturing the same, and composite materials. [Background technology]

[0002] Alloy foils are used in a variety of applications, including electronic components. Alloy foils are classified into rolled alloy foils and electrolytic alloy foils based on their manufacturing methods. Rolled alloy foil is an alloy foil manufactured by the rolling method. Specifically, it is produced by melting and casting alloy raw materials, followed by rolling and pickling annealing. However, the rolling method has the problem of being costly to manufacture because it requires multiple rolling processes to control the desired thickness. Electrolytic alloy foil is an alloy foil manufactured by an electrolytic method. Specifically, electrolytic alloy foil can be deposited on a cathode by performing electroplating in a plating solution containing multiple metal ions. In particular, by using a cylindrical metal drum cathode as the cathode, electroplating is performed to a predetermined thickness while rotating the metal drum cathode, and then it is wound up to continuously manufacture electrolytic alloy foil. Unlike the rolling method, the electrolytic method has the advantage that production efficiency increases as the thickness of the alloy foil decreases.

[0003] In recent years, with the demand for miniaturization and weight reduction of electronic components, there has been a need to reduce the thickness of alloy foils used in such components. When manufacturing thin alloy foils, it is desirable to use the electrolytic method as described above from the standpoint of production efficiency. However, Ni-Cr alloy foils containing nickel and chromium are difficult to manufacture using electrolytic methods because the deposition potentials of chromium and nickel are significantly different, and chromium is easily oxidized.

[0004] On the other hand, electroplating using a deep eutectic solvent containing choline chloride and ethylene glycol has been proposed as a method for producing Fe-Ni-Cr alloys (Non-Patent Document 1). In addition, a method of evaporation in argon has been proposed as a method for producing Cr-Ni alloy particles (Non-Patent Document 2). [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] G. Saravanan et al., “Electrodeposition of Fe-Ni-Cr alloy from Deep Eutectic System containing Choline chloride and Ethylene Glycol”, Int. J. Electrochem, Sci., Vol. 6, pp. 1468-1478, 2011 [Non-Patent Document 2] N. Yukawa and 4 others, "Structure of Chromium-Rich Cr-Ni, Cr-Fe, Cr-Co and Cr-Ni-Fe Alloy Particles Made by Evaporation in Argon," Metallurgical Transactions, Vol. 3, pp. 887-895, 1972 [Overview of the project] [Problems that the invention aims to solve]

[0006] The present invention has been made to solve the above-mentioned problems, and aims to provide an electrolytic Ni-Cr alloy foil that can be manufactured by an electrolytic method, a method for manufacturing the same, and a composite member comprising the electrolytic Ni-Cr alloy foil. [Means for solving the problem]

[0007] As a result of intensive research to solve the above problems, the present inventors have found that an electrolytic Ni-Cr alloy foil can be produced by performing electrolytic treatment at a predetermined current density using a predetermined plating bath, and have completed the present invention. Further, the present inventors have found that the electrolytic Ni-Cr alloy foil produced in this way has specific characteristics, and have completed the present invention.

[0008] That is, the present invention is 5 an electrolytic Ni-Cr alloy foil having a composition consisting of ~95% by mass of Ni, 5 ~95% by mass of Cr and impurities, and having a brightness L * of 30 or more.

[0009] Further, the present invention is A method for producing the aforementioned electrolytic Ni-Cr alloy foil, a plating bath containing Ni ions, Cr ions and choline ions, the balance being water, chloride ions and impurities, wherein the molar ratio of the Ni ions to the Cr ions is 0.001 to 0.150, and the molar ratio of the choline ions to the Cr ions is 1.00 to 3.00, and performing electrolytic treatment at a current density of 10 mA / cm 2 or more and less than 1000 mA / cm 2 is a method. The <0000***>

[0010] Furthermore, the present invention is a composite member including a base material and the electrolytic Ni-Cr alloy foil formed on the base material.

Advantages of the Invention

[0011] According to the present invention, it is possible to provide an electrolytic Ni-Cr alloy foil that can be produced by an electrolytic method, a method for producing the same, and a composite member including the electrolytic Ni-Cr alloy foil.

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be specifically described. The present invention is not limited to the following embodiments, and it should be understood that modifications, improvements, etc. may be appropriately added to the following embodiments based on the ordinary knowledge of those skilled in the art without departing from the gist of the present invention, and such modified and improved embodiments also fall within the scope of the present invention.

[0013] The electrolytic Ni-Cr alloy foil according to an embodiment of the present invention has a composition consisting of Ni, Cr, and impurities. Here, in this specification, "electrolytic Ni-Cr alloy foil" means a Ni-Cr alloy foil produced by an electrolytic method. Also, "Ni-Cr alloy foil" means an alloy foil having Ni and Cr as alloy components.

[0014] The Ni content in the electrolytic Ni-Cr alloy foil is not particularly limited, but preferably exceeds 0% by mass and is less than 100% by mass, more preferably 1 - 99% by mass, still more preferably 3 - 97% by mass, and particularly preferably 5 - 95% by mass. By controlling the Ni content within such a range, it becomes easier to ensure the characteristics of the Ni-Cr alloy (such as heat resistance and corrosion resistance, etc.). Here, the chemical composition such as the Ni content of the electrolytic Ni-Cr alloy foil can be measured by wet analysis.

[0015] The Cr content in the electrolytic Ni-Cr alloy foil is not particularly limited, but preferably exceeds 0% by mass and is less than 100% by mass, more preferably 1 - 99% by mass, still more preferably 3 - 95% by mass, and particularly preferably 5 - 91% by mass. By controlling the Cr content within such a range, it becomes easier to ensure the characteristics of the Ni-Cr alloy (such as heat resistance and corrosion resistance, etc.).

[0016] The impurities contained in the electrolytic Ni-Cr alloy foil are components mixed in due to the raw materials of the plating bath and various factors in the manufacturing process when manufacturing the electrolytic Ni-Cr alloy foil, and are allowed within a range that does not adversely affect the present invention. The impurities are not particularly limited, but may include Cl. Cl mainly originates from the raw materials of the plating bath. Therefore, when chlorides are used as the raw materials of the plating bath, electrolytic Ni-Cr alloy foils often contain Cl. The Cl content in the electrolytic Ni-Cr alloy foil generally exceeds 0% by mass, for example, 0.001% by mass or more, 0.003% by mass or more, or 0.005% by mass or more. On the other hand, the upper limit of the Cl content is not particularly limited as long as it does not affect the properties of the Ni-Cr alloy, but generally it is 0.10% by mass or less, for example, 0.08% by mass or less, 0.05% by mass or less, or 0.03% by mass or less.

[0017] In addition, the electrolytic Ni-Cr alloy foil may further contain one or more selected from O, S, C, and P as impurities. As described above, these components are mixed due to the raw materials of the plating bath and various factors in the manufacturing process. The contents of O, S, C, and P in the electrolytic Ni-Cr alloy foil are preferably as low as possible, but generally they are 0.10% by mass or less, for example, 0.08% by mass or less or 0.05% by mass or less.

[0018] The electrolytic Ni-Cr alloy foil according to the embodiment of the present invention has a lightness L * of 30 or more, preferably 50 or more, more preferably 60 or more, and still more preferably 70 or more. By controlling the lightness L * within this range, the amount of impurities contained in the electrolytic Ni-Cr alloy foil can be reduced (suppressing the decomposition of the raw materials of the plating bath and their inclusion in the electrolytic Ni-Cr alloy foil). The upper limit of the lightness L * is not particularly limited, but generally it is 90 or less, preferably 85 or less, and more preferably 80 or less. Here, in this specification, "lightness L * " means the lightness L * a * b * in the L * a * b colorimetric system defined in JIS Z8781-4:2013. The lightness L* This can be measured using a commercially available colorimeter.

[0019] The thickness of the electrolytic Ni-Cr alloy foil according to the embodiment of the present invention is not particularly limited, but is preferably 100 μm or less, more preferably 80 μm or less, even more preferably 60 μm or less, and particularly preferably 50 μm or less. The lower limit of the thickness can be appropriately set depending on the application of the electrolytic Ni-Cr alloy foil, but is generally 0.5 μm or more, preferably 1 μm or more.

[0020] In the embodiment of the present invention, the electrolytic Ni-Cr alloy foil preferably has a metal structure containing a δ phase. By having a metal structure containing a δ phase, the crystal grains can be refined by the pinning effect of the δ phase. As a result, the hardness of the electrolytic Ni-Cr alloy foil can be improved. The volume fraction of the δ phase in the electrolytic Ni-Cr alloy foil is not particularly limited, but is preferably 0.5% or more, more preferably 1% or more. Within this range of δ phase volume fraction, the pinning effect due to the δ phase can be obtained. On the other hand, the upper limit of the δ phase volume fraction is preferably 98% or less, more preferably 95% or less. Here, in this specification, the "volume fraction of the δ phase" can be measured by SEM-EBSD. In SEM-EBSD measurement, an electrolytic Ni-Cr alloy foil is cut to a predetermined size, embedded in resin so that the surface of the electrolytic Ni-Cr alloy foil is exposed, then mechanically polished in a wet manner to a mirror finish, and finally the outermost processing strain layer is removed by electropolishing to prepare a sample for measurement. Next, a 250 × 250 μm area is observed using this sample with an acceleration voltage of 15 kV. A JSM-7000F manufactured by JEOL Ltd. can be used for observation. Next, an EBSD crystal orientation map image is obtained using a crystal orientation analysis system. A PEGASUS2300 manufactured by TSL can be used as the crystal orientation analysis system. Next, the crystal grains of the δ phase are identified using analysis software, and the total area of ​​the δ phase is determined. A OIM-Data Collection 4 manufactured by TSL can be used as the analysis software. After that, the volume fraction of the δ phase is determined according to the following formula. Volume fraction of the δ phase (%) = Total area of ​​the δ phase / Area of ​​the observation field × 100

[0021] In the embodiment of the present invention, the electrolytic Ni-Cr alloy foil preferably has an average crystal grain size of 5 μm or less, and more preferably 4 μm or less. By controlling the average crystal grain size within this range, the hardness of the electrolytic Ni-Cr alloy foil can be stably improved. On the other hand, the lower limit of the average crystal grain size is not particularly limited, but is generally 0.1 μm or more, preferably 0.5 μm or more. In this specification, the "average grain size" can be measured by SEM-EBSD, similar to the volume fraction of the δ phase. The SEM-EBSD measurement method is as described above, but the average grain size can be determined using analysis software. Specifically, the analysis software approximates the exposed grains on the measurement surface into squares of the same area, and the lengths of the sides are determined. The average grain size is then defined as the average value obtained by averaging the side lengths of all grains within the observation field.

[0022] The electrolytic Ni-Cr alloy foil according to the embodiment of the present invention preferably has a Vickers hardness of 300 HV or higher, and more preferably 320 HV or higher. A Vickers hardness within this range indicates good hardness for the electrolytic Ni-Cr alloy foil, and it can be used without problems in various applications. On the other hand, the upper limit of the Vickers hardness is not particularly limited, but is generally 1000 HV or lower, preferably 800 HV or lower. In this specification, "Vickers hardness" can be determined by cutting a test piece from electrolytic Ni-Cr alloy foil and using a Vickers hardness tester in accordance with JIS Z2244:2009. The load used is 5g. The Vickers hardness is measured at five arbitrary points, and the average value is used as the result.

[0023] The electrolytic Ni-Cr alloy foil according to the embodiment of the present invention can be manufactured by performing an electrolytic treatment using a plating bath (plating solution) containing Ni ions, Cr ions, and choline ions, with the remainder being water, chloride ions, and impurities. The electrolytic Ni-Cr alloy foil manufactured in this manner is crack-free and exhibits practically sufficient ductility. Here, chloride ions are ions derived from the sources of Ni ions, Cr ions, and choline ions. Impurities are other components contained in the sources or components introduced due to various factors in the manufacturing process, and are acceptable as long as they do not adversely affect the present invention.

[0024] The plating bath has a molar ratio of Ni ions to Cr ions of 0.001 to 0.150, preferably 0.003 to 0.130, more preferably 0.005 to 0.120, and particularly preferably 0.008 to 0.110. Furthermore, the plating bath has a molar ratio of choline ions to Cr ions of 1.00 to 3.00, preferably 1.20 to 2.80, more preferably 1.30 to 2.70, and particularly preferably 1.50 to 2.50. By controlling the above molar ratios within these ranges, it becomes possible to form electrolytic Ni-Cr alloy foil by electrolytic treatment.

[0025] The Ni ion content in the plating bath is not particularly limited as long as the above molar ratio is satisfied, but is preferably more than 0 mol% and 2.00 mol% or less, more preferably 0.01 to 1.80 mol%, and even more preferably 0.03 to 1.50 mol%. Similarly, the Cr ion content is not particularly limited as long as the above molar ratio is satisfied, but is preferably 2.00 to 20.00 mol%, more preferably 2.50 to 18.00 mol%, and even more preferably 3.00 to 15.00 mol%. Furthermore, the choline ion content is not particularly limited as long as the above molar ratio is satisfied, but is preferably 3.00 to 40.00 mol%, more preferably 4.00 to 30.00 mol%, and even more preferably 5.00 to 20.00 mol%. By controlling the content of each ion within the above ranges, electrolytic Ni-Cr alloy foil can be stably formed by electrolytic treatment.

[0026] The source of Ni ions, Cr ions, and choline ions is not particularly limited as long as it is soluble in water, but chlorides (nickel chloride hexahydrate, chromium chloride hexahydrate, and choline chloride) are preferred. Since chlorides are easily soluble in water, using chlorides as a source allows for the stable formation of electrolytic Ni-Cr alloy foil by electrolytic treatment.

[0027] The conditions for electrolytic treatment are a current density of 10 mA / cm². 2 More than 1000mA / cm 2 It is necessary to control it to less than 10 mA / cm². 2 If the current density is less than 1000 mA / cm², the ion consumption rate on the substrate (electrode) surface where the electrolytic Ni-Cr alloy foil is formed will not be stable, making it difficult to form a homogeneous electrolytic Ni-Cr alloy foil. 2 If the current density exceeds this level, the components of the plating bath will decompose, and components such as sulfur will be mixed into the electrolytic Ni-Cr alloy foil as impurities. From the perspective of stably producing homogeneous electrolytic Ni-Cr alloy foil with few impurities, the current density should be 15-800 mA / cm². 2 It is preferable to do so, with a current of 20-500 mA / cm². 2 It is preferable to do so.

[0028] The processing time in the electrolytic treatment is not particularly limited and can be adjusted according to the thickness of the electrolytic Ni-Cr alloy foil being produced, but is generally 1 to 1000 minutes, preferably 3 to 800 minutes. The temperature of the plating bath in the electrolytic treatment is not particularly limited and is generally 0 to 110°C, but considering the productivity of electrolytic Ni-Cr alloy foil, it is preferably 50 to 95°C. Other conditions in the electrolytic treatment are not particularly limited and should be set appropriately according to the type of electrolytic treatment equipment used.

[0029] In electrolytic processes, a metal drum is used as the electrode (cathode) for the continuous industrial production of electrolytic Ni-Cr alloy foil. By rotating the metal drum and performing electrolytic processing (electroplating) to a predetermined thickness, and then winding it up, electrolytic Ni-Cr alloy foil can be continuously produced.

[0030] The electrolytic Ni-Cr alloy foil produced in this manner has high production efficiency and possesses properties (hardness, homogeneity, etc.) comparable to rolled Ni-Cr alloy foil produced by rolling, making it suitable for use in various applications such as electronic components (e.g., printed circuit boards).

[0031] An embodiment of the present invention comprises a substrate and an electrolytic Ni-Cr alloy foil formed on the substrate. This composite material allows for the formation of an electrolytic Ni-Cr alloy foil as an electroplated layer by using the substrate as an electrode (cathode) during the electrolytic treatment process. Furthermore, this composite component can be manufactured by first producing an electrolytic Ni-Cr alloy foil using a metal drum as the electrode (cathode), and then bonding this electrolytic Ni-Cr alloy foil to a substrate. The bonding method between the electrolytic Ni-Cr alloy foil and the substrate is not particularly limited and can be done by pressure bonding or adhesive.

[0032] The base material used in composite components is not particularly limited; an appropriate material should be selected according to the application. Examples of base materials include metals, resins, and ceramics. [Examples]

[0033] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

[0034] (Examples 1-4 and Comparative Examples 1-5) A plating solution (plating bath) was prepared by adding nickel chloride hexahydrate as the source of Ni ions, chromium chloride hexahydrate as the source of Cr ions, and choline chloride as the source of choline ions to water and mixing and stirring so that the content (mol%) and molar ratio of each ion were as shown in Table 1. Next, the plating solution was placed in a 500 mL beaker, and the electrodes were positioned. A Pt plate was used as the anode and a Ti plate as the cathode, and they were placed opposite each other with a distance of 50 mm between them. The area of ​​each electrode was 1 cm². 2 The size was set to (10mm x 10mm). Without stirring the plating solution, the current density and plating bath temperature were set to the values ​​shown in Table 1, and electrolytic treatment was performed for 100 minutes to form an electrolytic alloy foil on the surface of the cathode. After the electrolytic treatment, the cathode was removed, washed with water, dried, and then the electrolytic alloy foil was peeled off the cathode with tweezers to obtain a sample.

[0035] [Table 1]

[0036] (Comparative Example 6) Ni-Cr alloy foil was manufactured by a rolling method. Specifically, ingots having the compositions shown in Table 2 were cast in a vacuum melting furnace, hot-rolled, and then repeatedly cold-rolled, annealed, and pickled until a thickness of 40 μm was achieved to produce rolled Ni-Cr alloy foil.

[0037] (Comparative Example 7) An electrolytic nickel foil was formed by using an aqueous nickel sulfamate solution as a plating bath and performing electrolytic treatment under the same conditions as in Example 1. The plating bath contained 3.37 mol% nickel ions, 0.32 mol% chloride ions, and 6.41 mol% sulfamate ions.

[0038] The samples obtained in the above examples and comparative examples were evaluated as follows. (composition) The composition of the sample was identified by wet analysis. (Thickness) The thickness of the sample was measured using a commercially available thickness measuring device. (Volume fraction of the δ phase) The sample was measured by SEM-EBSD according to the method described above, and the volume fraction of the δ phase was determined. (Average grain size) The sample was measured by SEM-EBSD according to the method described above, and the average grain size was determined. (Lightness L * ) Brightness L according to the method described above * We measured it. (Vickers hardness) The Vickers hardness was measured according to the method described above.

[0039] The results of each of the above evaluations are shown in Table 2.

[0040] [Table 2]

[0041] As shown in Table 2, in Examples 1 to 4, electrolytic treatment was used to produce electrolytic Ni-Cr alloy foil that had hardness equal to or greater than that of rolled Ni-Cr alloy foil (Comparative Example 6), and had a low amount of impurities. Furthermore, the electrolytic Ni-Cr alloy foils of Examples 1 to 4 had a brightness of L * In terms of performance, it was at the same level as rolled Ni-Cr alloy foil (Comparative Example 6) and electrolytic Ni foil (Comparative Example 7), and its appearance was also comparable. In contrast, in Comparative Example 1, the current density was too high, causing the components of the plating solution to decompose and mix in, resulting in a black (brightness L) finish with a large amount of impurities. * (The value was small) resulting in electrolytic Ni-Cr alloy foil. In Comparative Example 2, the molar ratio of Ni ions to Cr ions (the molar ratio of Ni / Cr ions) was too small, resulting in an electrolytic Cr foil that did not contain Ni. In Comparative Example 3, the molar ratio of Ni / Cr ions was too high, resulting in an electrolytic nickel foil that did not contain Cr. In Comparative Example 4, the molar ratio of choline ions to Cr ions (choline / Cr ion molar ratio) was too small, so oxide formation was not suppressed, and Fe and Cr oxides and hydroxides were mixed in, resulting in a black color (brightness L). * (The value was small) resulting in electrolytic Ni-Cr alloy foil. In Comparative Example 5, the molar ratio of choline / Cr ions was too high, resulting in a highly viscous plating bath. This prevented a stable current flow, making it impossible to manufacture Ni-Cr alloy foil. Therefore, various evaluations could not be performed on Comparative Example 5.

[0042] As can be seen from the above results, the present invention provides an electrolytic Ni-Cr alloy foil that can be manufactured by an electrolytic method, a method for manufacturing the same, and a composite member comprising the electrolytic Ni-Cr alloy foil.

Claims

1. Having a composition consisting of 5 to 95% by mass of Ni, 5 to 95% by mass of Cr, and impurities, with a brightness of L * Electrolytic Ni-Cr alloy foil with a coefficient of 30 or higher.

2. The electrolytic Ni-Cr alloy foil according to claim 1, wherein the impurity contains more than 0% by mass and 0.10% by mass or less of Cl.

3. The electrolytic Ni-Cr alloy foil according to claim 1 or 2, wherein the impurities include one or more selected from 0.10% by mass or less of O, 0.10% by mass or less of S, 0.10% by mass or less of C, and 0.10% by mass or less of P.

4. An electrolytic Ni-Cr alloy foil according to any one of claims 1 to 3, wherein the thickness is 100 μm or less.

5. An electrolytic Ni-Cr alloy foil according to any one of claims 1 to 4, having a metallic structure containing a δ phase.

6. The electrolytic Ni-Cr alloy foil according to any one of claims 1 to 5, wherein the average crystal grain size is 5 μm or less.

7. An electrolytic Ni-Cr alloy foil according to any one of claims 1 to 6, wherein the Vickers hardness is 300 HV or higher.

8. A composite member comprising a base material and an electrolytic Ni-Cr alloy foil according to any one of claims 1 to 7 formed on the base material.

9. A method for producing an electrolytic Ni-Cr alloy foil according to any one of claims 1 to 7, Using a plating bath containing Ni ions, Cr ions, and Choline ions, with the remainder being water, chloride ions, and impurities, where the molar ratio of Ni ions to Cr ions is 0.001 to 0.150 and the molar ratio of Choline ions to Cr ions is 1.00 to 3.00, at a current of 10 mA / cm². 2 More than 1000mA / cm 2 A method for performing electrolytic treatment at a current density of less than a certain level.

10. The method according to claim 9, wherein the Ni ions are greater than 0 mol% and less than or equal to 2.00 mol%, the Cr ions are 2.00 to 20.00 mol%, and the choline ions are 3.00 to 40.00 mol%.

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